An explosion-proof or flameproof container includes at least one base body having an opening surrounded by an opening edge and a cover part that can be placed onto or inserted into the opening edge. Such containers serve, for instance, to receive electronic devices and may be arranged as individual containers or also in groups. The cover part and the base body are for instance screwed to one another to firmly fasten the cover part to the base body. The contact surfaces formed between the cover part and the base body especially in the area of the opening edge have a flat design as a rule and are protected by application of a protecting agent, such as a lubricant, e.g. against corrosion. If one wants to open the container after some time, this may be relatively difficult because of the adhesion between the base body and the cover part. The protecting agent can almost have the effect of an adhesive.
As a rule, the attempt is made to form a gap between cover part and base body by using a tool, the gap being then used for the further opening of the container. When a corresponding force is applied, the cover part or the base body may get damaged particularly in the area of the opening edge, so that when the container is closed again, it is no longer possible to guarantee explosion protection or flame proofness. This might lead to increased costs, to the repair of the container or to an unsafe container.
It is known from practice that tools are, for example, used for forming the corresponding gap, the tools being made of a softer material than the material of the container. Although damage during formation of the gap can thereby mainly be avoided, it is still rather difficult to open the container.